solr搜索提示，将词添加到词库中

solr wiki： http://wiki.apache.org/solr/Suggester/

     实现对搜索时关键字的提示，同时扩展，将词库中未有的关键词添加到词库中，目前不支持去重功能。

一、solrconfig.xml 配置

     在solrconfig.xml配置文件中添加 “关键词提示” 组件

	<searchComponent name="suggest" class="com.netboy.demo.function.SpellCheckAndLoadComponent">  
	  <lst name="spellchecker">  
	    <str name="name">suggest</str>  
	    <str name="classname">org.apache.solr.spelling.suggest.Suggester</str>  
	    <str name="lookupImpl">org.apache.solr.spelling.suggest.tst.TSTLookup</str>  
	    <str name="field">title</str>
	    <str name="sourceLocation">stopwords.txt</str>
	    <str name="size">4</str>
	    <!-- <float name="threshold">0.005</float> -->
	     <str name="buildOnCommit">true</str>
	  </lst>  
	</searchComponent> 

	<requestHandler name="/suggest" class="org.apache.solr.handler.component.SearchHandler">  
	 <lst name="defaults">  
	   <str name="spellcheck">true</str>
	   <str name="spellcheck.dictionary">suggest</str>  
	   <str name="spellcheck.count">5</str>  
	   <str name="spellcheck.onlyMorePopular">true</str>  
	   <str name="spellcheck.collate">true</str>      
	 </lst>  
	 <arr name="components">  
	   <str>suggest</str>  
	 </arr>
	</requestHandler>

stopwords.txt内容如下：

jetty
netty
淘宝
taobao
水杯
章法
天龙八部
虚竹
木婉清
段誉
章
人
人 民
嫁了人

二、 扩展SpellCheckComponent

自定义类SpellCheckAndLoadComponent类，实现:  solr搜索提示，将词添加到词库中

代码如下：

import java.io.BufferedWriter;
import java.io.FileNotFoundException;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Set;

import org.apache.solr.common.params.SolrParams;
import org.apache.solr.common.util.NamedList;
import org.apache.solr.core.SolrCore;
import org.apache.solr.handler.component.ResponseBuilder;
import org.apache.solr.handler.component.SpellCheckComponent;
import org.apache.solr.request.SolrQueryRequest;
import org.eclipse.jetty.util.ConcurrentHashSet;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * 返回已经有的提示词，如果没有则将该词添加到词库中
 * 
 * @author 2013-7-13下午10:09:36
 */
public class SpellCheckAndLoadComponent extends SpellCheckComponent {
	private static final Logger logger = LoggerFactory.getLogger(SpellCheckAndLoadComponent.class);

	private static ConcurrentHashSet<String> spellSet = new ConcurrentHashSet<String>();
	private BufferedWriter out;
	private int size = 99;
	private String field;

	@Override
	public void init(NamedList args) {
		super.init(args);
		Object o = args.get("spellchecker");
		String fileStr = null;
		if(o != null && o instanceof NamedList) {
			NamedList temp = (NamedList) o;
			fileStr = (String) temp.get("sourceLocation");
			String sizeStr = (String) temp.get("size");
			field = (String) temp.get("field");

			if(sizeStr != null) {
				size = Integer.parseInt(sizeStr);
			}
			logger.info("the dictionary is " + fileStr);

		}
		synchronized(this) {
			if(fileStr != null) {
				try {
					out = new BufferedWriter(new FileWriter(fileStr, true));
				} catch(FileNotFoundException e) {
					e.printStackTrace();
				} catch(IOException e) {

					e.printStackTrace();
				}
			}
		}

	}

	@Override
	public void inform(SolrCore solrCore) {
		super.inform(solrCore);
		synchronized(this) {
			if(spellSet == null) {
				spellSet = new ConcurrentHashSet<String>();
			}
		}
	}

	@Override
	public void process(ResponseBuilder rb) {
		String words = null;
		try {
			super.process(rb);
			SolrQueryRequest sqr = rb.req;
			SolrParams param = sqr.getParams();
			words = param.get("q").trim();
			
			String[] subString = words.split(":");
			if(subString[0].equals(field)) {
				words = subString[1].trim();
				synchronized(this) {
					spellSet.add(words);
					if(spellSet.size() >= size) {
						pushFile(spellSet);
						spellSet.clear();
					}
				}
			}

		} catch(IOException e) {

			logger.warn("spellCheck had some error" + e);
		}
	}

	public void pushFile(Set<String> set) {
		for(String str : set) {
			if(str != null) {
				try {
					out.write(str);
					out.newLine();
					out.flush();

				} catch(IOException e) {
					logger.warn("error in writing dictionary" + e);
				}
			}
		}
	}

	@Override
	public void finishStage(ResponseBuilder rb) {
		super.finishStage(rb);
		pushFile(spellSet);
		synchronized(out) {
			try {
				out.close();
			} catch(IOException e) {
				logger.info("close the FileOutputStream" + e);
			}
		}

		spellSet.clear();
	}
}

三、运行

第一次运行：http://127.0.0.1:8989/auction/suggest?q=title:%E4%BA%BA&spellcheck=on&spellcheck.build=true

返回结果：

如果词库中没有关键词如： http://127.0.0.1:8989/auction/suggest?q=title:电子科大&spellcheck=on&spellcheck.build=true

     返回结果： 

第二次运行： http://127.0.0.1:8989/auction/suggest?q=title:电&spellcheck=on&spellcheck.build=true

返回结果：

四、客户端连接

public class SpellCheckTest {
	public static void main(String[] args) {
		SolrServer solrServer = new HttpSolrServer("http://127.0.0.1:8989/auction");

		// http://127.0.0.1:8989/auction/suggest?q=人&spellcheck=on&spellcheck.build=true 
		SolrQuery params = new SolrQuery();

		String token = "人";
		params.set("qt", "/suggest");
		params.set("q", token);
		params.set("spellcheck", "true");
		params.set("spellcheck.build", "true");

		QueryResponse response = null;

		try {
			response = solrServer.query(params);
		} catch(SolrServerException e) {
			System.err.println(e.getMessage());
			e.printStackTrace();
		} catch(Exception e) {
			System.err.println(e.getMessage());
			e.printStackTrace();
		} finally {
			solrServer.shutdown();
		}

		SpellCheckResponse spellCheckResponse = response.getSpellCheckResponse();
		if(spellCheckResponse != null) {
			List<Suggestion> suggestionList = spellCheckResponse.getSuggestions();
			for(Suggestion suggestion : suggestionList) {
				System.out.println("Suggestions NumFound: " + suggestion.getNumFound());
				System.out.println("Token: " + suggestion.getToken());
				System.out.print("Suggested: ");
				List<String> suggestedWordList = suggestion.getAlternatives();
				for(String word : suggestedWordList) {
					System.out.println(word);
				}
				System.out.println();
			}

			System.out.println("查询耗时：" + response.getQTime());
			solrServer.shutdown();
		}
	}
}

Suggestions NumFound: 1
Token: 人
Suggested: 人 民

查询耗时：6